Signals from the adipose tissue determine daily hunger rhythms

A Lübeck project shows that the fat tissue secreted hormone adiponectin controls the daily rhythm of food intake by resetting circadian clocks in the hypothalamus.

A Lübeck project shows that the fat tissue secreted hormone adiponectin controls the daily rhythm of food intake by resetting circadian clocks in the hypothalamus.

We usually are more hungry during the day while getting through the night asleep - and thus fasting - free from hunger attacks. This daily appetite rhythm is controlled by molecular, so-called circadian clocks in the brain, which run in sync with the day-night rhythm. If these clocks are disturbed, e.g. in the case of night shift workers or under high-fat diet conditions, appetite and eating phases shift into the night, which in turn leads to an increased risk of metabolic and cardiovascular diseases.

Using mouse experiments, Lübeck researchers led by Anthony Tsang, Christiane Koch and Henrik Oster from the Institute of Neurobiology at the CBBM were able to show how these rhythms of energy consumption and clock function communicate with each other. Like humans, mice produce the hormone adiponectin in their white adipose tissues. This adiponectin rhythms adjusts molecular clocks in the hypothalamus, which are responsible for appetite regulation. In obese patients or after a high-fat meal the adiponectin rhythm is disturbed - and with it the rhythm of food intake. However – as Tsang and colleagues show – if one artificially restores the adiponectin rhythm under these conditions, the daily eating rhythm normalises and the animals lose weight despite the high-fat food.

"Of course, comparable studies in humans are still pending. However, our results already suggest that adiponectin chronotherapy could be an approach to favorably influence appetite rhythms - and thus weight regulation - for example in obesity patients," says Prof. Oster, the head of the study.

The project was supported financially by the German Research Foundation and the Volkswagen Foundation. Colleagues from the Institute for Diabetes and Metabolism were also involved.

Publication: An adipokine feedback regulating diurnal food intake rhythms in mice. Tsang AH, Koch CE, Kiehn JT, Schmidt CX, Oster H.Elife. 2020 Jul 9; 9: e55388. doi: 10.7554 / eLife.55388. Online ahead of print.

Contact: Prof. Dr. Henrik Oster / henrik.oster@uni-luebeck.de, https://www.neurobio.uni-luebeck.de/